Charcot-Marie-Tooth disease: genetic subtypes in the Sardinian population.

Charcot-Marie-Tooth disease (CMT) is characterised by great variability of genetic subtypes. This study aimed to assess the genetic subtypes of CMT disease in the Sardinian population. Genetic screening was performed for CMT cases (CMT1, CMT2, and hereditary neuropathy with susceptibility to pressure palsies [HNPP]).

Phenotypic variability related to C9orf72 mutation in a large Sardinian kindred.

We investigated intrafamilial phenotypic variability in carriers of the C9orf72 mutation, analysing clinical, neuropsychological and imaging characteristics of various members from a large Sardinian kindred with FTD or ALS. We compared these with those of C9 + patients in our ALS and FTD cohorts. Results showed that three patients carried the C9orf72 mutation: two with ALS and one with FTD and Parkinsonism.

C9ORF72 intermediate repeat expansion in patients affected by atypical parkinsonian syndromes or Parkinson's disease complicated by psychosis or dementia in a Sardinian population.

The hexanucleotide repeat expansion GGGGCC in the C9ORF72 gene larger than 30 repeats has been identified as a major genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Recent papers investigated the possible pathogenic role and associated clinical phenotypes of intermediate C9ORF72 repeat expansion ranging between 20 and 30 repeats. Some studies suggested its pathogenicity for typical Parkinson's disease (PD), atypical parkinsonian syndromes, FTD with/without parkinsonism, and ALS with/without parkinsonism or with/without dementia.

Clinical phenotypes and radiological findings in frontotemporal dementia related to TARDBP mutations.

It has been shown that different genes could be associated with distinctive clinical and radiological phenotypes of FTD. TARDBP gene has been described worldwide in few cases of FTD so its phenotype is still unclear. The objective is to study the clinical and radiological characteristics of TARDBP-related FTD.

Constructional apraxia in frontotemporal dementia associated with the C9orf72 mutation: broadening the clinical and neuropsychological phenotype.

In our study we analysed clinical and neuropsychological data in a cohort of 57 Sardinian patients with FTD (55 apparently unrelated and two belonging to the same family), who underwent genetic screening for the C9orf72 mutation. Eight out of 56 patients were found positive for the C9orf72 mutation representing 14% of the entire cohort and 31.6% of the familial cases (6/19).

The p.A382T TARDBP gene mutation in Sardinian patients affected by Parkinson's disease and other degenerative parkinsonisms.

Based on our previous finding of the p.A382T founder mutation in ALS patients with concomitant parkinsonism in the Sardinian population, we hypothesized that the same variant may underlie Parkinson's disease (PD) and/or other forms of degenerative parkinsonism on this Mediterranean island. We screened a cohort of 611 patients with PD (544 cases) and other forms of degenerative parkinsonism (67 cases) and 604 unrelated controls for the c.

Vitamin D responsive elements within the HLA-DRB1 promoter region in Sardinian multiple sclerosis associated alleles.

Vitamin D response elements (VDREs) have been found in the promoter region of the MS-associated allele HLA-DRB1*15:01, suggesting that with low vitamin D availability VDREs are incapable of inducing *15:01 expression allowing in early life autoreactive T-cells to escape central thymic deletion. The Italian island of Sardinia exhibits a very high frequency of MS and high solar radiation exposure. We test the contribution of VDREs analysing the promoter region of the MS-associated DRB1 *04:05, *03:01, *13:01 and *15:01 and non-MS-associated *16:01, *01, *11, *07:01 alleles in a cohort of Sardinians (44 MS patients and 112 healthy subjects).

Parkin Exon Rearrangements and Sequence Variants in LRRK2 Mutations Carriers: Analysis on a Possible Modifier Effect on LRRK2 Penetrance.

Mutations in LRRK2 represent the most common causes of Parkinson's disease (PD) identified to date, but their penetrance is incomplete and probably due to the presence of other genetic or environmental factors required for development of the disease. We analyzed the presence of parkin sequence variants (mutations or polymorphisms) and exon rearrangements in LRRK2 mutations carriers (both PD patients and unaffected relatives) in order to detect a possible modifier effect on penetrance. Eight families with nine PD patients with heterozygous LRRK2 mutations (identified within 380 Sardinian PD patients screened for the presence of the five most common LRRK2 mutations) and sixteen additional relatives were genetically investigated for the presence of LRRK2 and parkin mutations.

Heat shock protein 27 R127W mutation: evidence of a continuum between axonal Charcot-Marie-Tooth and distal hereditary motor neuropathy.

Background: Heat shock protein 27 (HSP27) mutations have been reported to cause both Charcot-Marie-Tooth disease (CMT) type 2F and distal hereditary motor neuropathy (dHMN) although never previously in a single family.

Objective: To analyse clinical and electrophysiological findings obtained in a single large Sardinian family bearing the HSP27 R127W mutation.

Methods: Twenty-one members of a five generation Sardinian family have been studied, including thirteen members affected by peroneal muscular atrophy and proved heterozygous for the known HSP27 R127W mutation.

Genetic analysis for five LRRK2 mutations in a Sardinian parkinsonian population: importance of G2019S and R1441C mutations in sporadic Parkinson's disease patients.

Mutations in the LRRK2 gene are the most common known cause of familial and sporadic Parkinson's disease (PD). Few studies performed to date to assess frequency of these mutations are actually only representative of specific areas. Here we study the frequency and clinical phenotype of LRRK2 G2019S, I2020T and R1441C/G/H mutations in 356 Sardinian patients with idiopathic PD and 208 controls.

mtDNA nt13708A variant increases the risk of multiple sclerosis.

Background: Mitochondrial DNA (mtDNA) polymorphism is a possible factor contributing to the maternal parent-of-origin effect in multiple sclerosis (MS) susceptibility.

Methods And Findings: In order to investigate the role of mtDNA variations in MS, we investigated six European MS case-control cohorts comprising >5,000 individuals. Three well matched cohorts were genotyped with seven common, potentially functional mtDNA single nucleotide polymorphisms (SNPs).

Genetic loci linked to type 1 diabetes and multiple sclerosis families in Sardinia.

Background: The Mediterranean island of Sardinia has a strikingly high incidence of the autoimmune disorders Type 1 Diabetes (T1D) and Multiple Sclerosis (MS). Furthermore, the two diseases tend to be co-inherited in the same individuals and in the same families. These observations suggest that some unknown autoimmunity variant with relevant effect size could be fairly common in this founder population and could be detected using linkage analysis.